Vacuum processing apparatus

ABSTRACT

A grease supply mechanism is provided inside a vacuum transfer chamber. The grease supply mechanism includes: a grease storage part in a bottomed cylindrical shape storing grease therein; and a movable cover covering an opening of the grease storage part and sliding while being in contact with an inner wall of the grease storage part. When the cover is pressed and moved, the grease is supplied into a grease inlet via a grease supply port.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a Divisional of and claims the benefit of priorityunder 35 U.S.C. §120 from U.S. Ser. No. 11/297,379, filed Dec. 9, 2005and claims the benefit of priority from the prior Japanese PatentApplication No. 2004-371049, filed on Dec. 22, 2004; the entire contentsof each which are incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a vacuum processing apparatus in whichthe transfer of an object to be processed such as, for example, asemiconductor wafer and vacuum processing such as etching and filmdeposition are performed under a vacuum atmosphere.

2. Description of the Related Art

As a conventionally known vacuum processing apparatus, there is a vacuumprocessing apparatus which applies, under a vacuum atmosphere, vacuumprocessing such as, for example, etching and film deposition to anobject to be processed such as, for example, a semiconductor wafer. Assuch a vacuum processing apparatus, also known is one in which atransfer mechanism is provided in a vacuum chamber (vacuum transferchamber) and an object to be processed such as a semiconductor wafer iscarried in this vacuum transfer chamber (see, for example, JapanesePatent Laid-open Application No. Hei 8-11940).

When the above-described vacuum processing apparatus includes, forexample, a mechanically operating mechanism such as a transfer mechanismprovided in the vacuum chamber, grease (vacuum grease) is sometimesapplied as a lubricant to a slide mechanism part and the like of thetransfer mechanism and the like provided in the vacuum chamber. In sucha case, periodic resupply of the grease to the slide mechanism part andthe like in the vacuum chamber is necessary. In the conventional vacuumapparatus, at the time of this grease resupply, the vacuum chamber isopened to the atmosphere and a worker injects the grease to apredetermined place by using a grease gun or the like.

However, the work of once opening the vacuum chamber, which has been setto the vacuum atmosphere, to the atmosphere and supplying the greasetakes time and trouble. Moreover, it takes time to set the vacuumchamber, which is once opened to the atmosphere, to the vacuumatmosphere again so as to allow the resumption of the vacuum processing.This has a problem of lowering the operating rate of the vacuumprocessing apparatus to worsen productivity.

Another problem is that the maintenance of the grease supply maypossibly be forgotten and a sliding operation with insufficient greaseis continued for a long period of time, which may possibly give a badeffect to the vacuum processing apparatus.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide a vacuum processingapparatus in which grease can be supplied to a predetermined placewithout opening a vacuum chamber to the atmosphere, thereby improvingthe operating rate of the vacuum processing apparatus to achieveimproved productivity, and in which the maintenance of the grease supplycan be performed without fail.

A vacuum processing apparatus according to an aspect of the presentinvention is a vacuum processing apparatus applying vacuum processing toan object to be processed under a vacuum atmosphere, the apparatusincluding: a vacuum chamber; and a grease supply mechanism provided inthe vacuum chamber to supply grease to a slide mechanism sliding in thevacuum chamber.

According to one embodiment of the vacuum processing apparatus of thepresent invention, the vacuum processing apparatus further includes acontrol unit which controls the grease supply mechanism to supply thegrease to the slide mechanism based on a timing for supplying the greaseto the slide mechanism, which is stored in the control unit.

According to one embodiment of the vacuum processing apparatus of thepresent invention, the slide mechanism is provided in a transfermechanism which transfers the object to be processed in the vacuumchamber.

According to one embodiment of the vacuum processing apparatus of thepresent invention, the slide mechanism is constituted of a ball screwand a ball nut included in the transfer mechanism.

A vacuum processing apparatus according to an aspect of the presentinvention includes: a plurality of vacuum process chambers in each ofwhich vacuum processing is applied to an object to be processed; avacuum transfer chamber connected to the vacuum process chambers viagate valves; a transfer mechanism transferring the object to beprocessed in the vacuum transfer chamber and having a grease inletopening into the vacuum transfer chamber; a grease supply mechanismprovided in the vacuum transfer chamber and including a grease storagepart and a grease supply port through which grease stored in the greasestorage part is supplied; and a control mechanism which moves thetransfer mechanism to bring the grease inlet into contact with thegrease supply port of the grease supply mechanism, and causes the greasestored in the grease storage part to be supplied to the grease inlet.

According to one embodiment of the vacuum processing apparatus of thepresent invention, the transfer mechanism includes a ball screw and aball nut provided in the vacuum transfer chamber, and the greasesupplied to the grease inlet is supplied to the ball screw and the ballnut.

According to one embodiment of the vacuum processing apparatus of thepresent invention, the control mechanism calculates a total drivenamount of the transfer mechanism driven by the ball screw and the ballnut and causes the grease to be supplied from the grease supplymechanism when the calculated total driven amount reaches apredetermined value.

According to one embodiment of the vacuum processing apparatus of thepresent invention, the control mechanism finds the total driven amountby calculating a total driven distance or a total driven time.

According to one embodiment of the vacuum processing apparatus of thepresent invention, the grease supply mechanism includes: a greasestorage part; and a movable cover covering an opening of the greasestorage part, sliding while being in contact with an inner wall of thegrease storage part, and having a grease supply port, and the cover ispressed and moved toward an inside of the grease storage part by apredetermined distance to cause a predetermined amount of the grease tobe supplied through the grease supply port.

According to one embodiment of the vacuum processing apparatus of thepresent invention, the grease supply mechanism includes: a greasestorage part; a movable piston sliding while being in contact with aninner wall of the grease storage part; and a bimetal connected to thepiston, and when temperature rises, the bimetal deforms to move thepiston, and causes grease in the grease storage part to be supplied.

According to one embodiment of the vacuum processing apparatus of thepresent invention, the slide mechanism is provided in a transfermechanism which transfers the object to be processed in the vacuumchamber.

According to one embodiment of the vacuum processing apparatus of thepresent invention, the slide mechanism is constituted of a ball screwand a ball nut included in the transfer mechanism, and the grease supplymechanism is provided adjacent to the ball nut. Alternatively, the slidemechanism is constituted of a rail and a slider of a linear guideincluded in the transfer mechanism, and the grease supply mechanism isprovided adjacent to a bearing mechanism of the slider.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a view roughly showing a whole structure of a vacuumprocessing apparatus according to an embodiment of the presentinvention.

FIG. 2 is a view showing a rough structure of an essential part of thevacuum processing apparatus shown in FIG. 1.

FIG. 3 is a view showing a rough structure of an essential part of thevacuum processing apparatus shown in FIG. 1.

FIG. 4 is a view showing a rough structure of an essential part of thevacuum processing apparatus shown in FIG. 1.

FIG. 5 is a view showing a rough structure of a grease supply mechanismof the vacuum processing apparatus shown in FIG. 1.

FIG. 6 is a view showing a rough structure of another grease supplymechanism.

FIG. 7A is a view showing the grease supply mechanism shown in FIG. 6 atroom temperature, and

FIG. 7B is a view showing the same at high temperature.

DESCRIPTION OF THE EMBODIMENTS

Hereinafter, an embodiment of the present invention will be describedwith reference to the drawings. FIG. 1 shows a whole structure of avacuum processing apparatus according to the embodiment of the presentinvention. As shown in FIG. 1, a vacuum transfer chamber 10 is providedin a center portion of a vacuum processing apparatus 1. Along the vacuumtransfer chamber 10, a plurality of (6 in this embodiment) vacuumprocess chambers 11 to 16 are arranged to surround the vacuum transferchamber 10.

In front of (the lower side in FIG. 1) of the vacuum transfer chamber10, two load lock chambers 17 are provided, and a transfer chamber 18for transferring a semiconductor wafer W in the atmosphere is providedin front of (the lower side in FIG. 1) of the load lock chambers 17. Infront of (the lower side in FIG. 1) of the transfer chamber 18, furtherprovided are a plurality of (3 in FIG. 1) mounting parts 19 on each ofwhich a cassette or a FOUP capable of housing a plurality ofsemiconductor wafers W is placed. On a side (left side in FIG. 1) of thetransfer chamber 18, an aligning mechanism 20 aligning the semiconductorwafer W by an orientation flat or a notch is provided.

Inside the vacuum transfer chamber 10, a transfer mechanism 50 isdisposed as shown in FIG. 2. The transfer mechanism 50 includes acarrier base 51 and two carrier arms 52, 53 rotatably andcontractibly/expandably provided on the carrier base 51.

As shown in FIG. 3 and FIG. 4, the carrier base 51 is movable along alongitudinal direction of the vacuum transfer chamber 10 by linearguides 60 and ball screws 61 provided on both sides thereof (only thoseon one side are shown in FIG. 3 and FIG. 4).

Each of the carrier arms 52, 53 holds one semiconductor wafer W and iscapable of carrying the semiconductor wafer W into/out of each of thevacuum process chambers 11 to 16 and the load lock chambers 17 shown inFIG. 1. Note that openings 11 a to 16 a shown in FIG. 2 are connectionportions connected to the vacuum process chambers 11 to 16 respectivelyvia not shown opening/closing mechanisms. Similarly, an opening 17 ashown in FIG. 2 is a connection portion connected to the load lockchambers 17 via a not shown opening/closing mechanism.

Further, one end of a duct arm (arm mechanism) 54 bending/stretchingaccording to the movement of the carrier base 51 is connected to thecarrier base 51, and the other end of the duct arm 54 is connected to abase member 10 a of the vacuum transfer chamber 10. Note that FIG. 3 andFIG. 4 show a state where structures such as the carrier arms 52, 53 onthe carrier base 51 are removed for easier understanding of thestructure of the carrier base 51 and the duct arm 54.

The duct arm 54 is constituted of a front part 54 a and a rear part 54 bwhich are rotatably connected to each other via a joint part 54 c, andthe connection portion connected to the carrier base 51 and theconnection portion connected to the base member 10 a are also rotatable.The duct arm 54, which itself does not have any driving source,bends/stretches in accordance with the movement of the carrier base 51.Note that FIG. 3 shows a state where the carrier base 51 has moved tothe vacuum process chambers 13, 14 side shown in FIG. 1 and the duct arm54 is in its most stretched state. Further, the front part 54 a and therear part 54 b of the duct arm 54 are connected to each other, with thefront part 54 a on an upper side of the rear part 54 b, and when theduct arm 54 is in a bent state, the front part 54 a is stacked on theupper side of the rear part 54 b, so that the duct arm 54 is foldedwithout any interference between the front part 54 a and the rear part54 b. Further, the inside of the duct arm 54 is hollow, and this hollowportion is a cable housing part 55 capable of housing cables and thelike and being set to a normal pressure atmosphere. Incidentally, thecables and the like refer to those connecting the inside and the outsideof the vacuum transfer chamber 10, for example, electric cables,inlet/exhaust tubes, tubes for temperature regulating mediumcirculation, and the like. Housing such cables and the like in the cablehousing part 55 which is the inside of the duct arm 54 makes it possibleto prevent gas or particles generated from the cables and the like fromcontaminating the inside of the vacuum transfer chamber 10.

As shown in FIG. 5, a grease supply mechanism 70 is disposed in thevacuum transfer chamber 10. The grease supply mechanism 70 is disposednear end portions of the aforesaid linear guide 60 and ball screw 61.The grease supply mechanism 70 is provided on a slider 63 on which thecarrier base 51 is placed, and it is capable of supplying grease (vacuumgrease) to a portion of a ball nut 62 screwed to the ball screw 61.Incidentally, as the grease (vacuum grease), usable are, for example,fluorinated grease (for example, DEMNUM Grease (trade name: DaikinIndustries, Ltd.)) and the like.

The grease supply mechanism 70 includes a cylindrical grease storagepart 71 storing grease G therein, and the grease storage part 71 isfixed to the base member 10 a of the vacuum transfer chamber 10 by anot-shown screw or the like, with its position being adjustable. Thegrease storage part 71 has a cover 72 covering an opening of the greasestorage part 71. The cover 72 is movable and slides while being incontact with an inner wall of the grease storage part 71, and has agrease supply port 73 formed near a center portion thereof. Further, anannular sealing member 74 which seals a gap between the cover 72 and aninner wall of the grease storage part 71 is slidably provided around thecover 72 to prevent a large amount of the grease from leaking from asliding portion.

Meanwhile, the slider 63 for moving the carrier base 51 along the linearguide 60 has a grease inlet 64 which is protrudingly provided so as tobe aligned with the grease supply port 73 of the grease supply mechanism70. The grease inlet 64 communicates with an inner part of the ball nut62 via a grease path 65. Incidentally, the grease inlet 64 and theaforesaid grease supply port 73 may have an opening/closing mechanismwhich opens/closes by a resilient force of a spring or the like. Inparticular, when highly volatile grease is used, it is preferable toprovide such an opening/closing mechanism to prevent the evaporation ofthe grease.

For resupply of the grease, the ball screws 61 are rotated by motors 66to move the carrier base 51 along the linear guides 60 together with thesliders 63, thereby bringing the grease inlet 64 into contact with thecover 72. Next, the carrier base 51 in this state is further movedtoward the cover 72 to press and move the cover 72, so that the greasein the grease storage part 71 is supplied into the grease inlet 64 viathe grease supply port 73. At this time, it is possible to control anamount of the supplied grease by a movement distance of the cover 72.

A movement range of the carrier base 51 and the slider 63 in a normaltransfer operation is up to such a position that the grease inlet 64does not come in contact with the cover 72. Therefore, the grease is notsupplied in the normal transfer operation.

The grease supply operation using the grease supply mechanism 70described above is controlled by a control device 100 centrallycontrolling the entire operations of the vacuum processing apparatus 1.Specifically, the control device 100 controls the driving of the motors66 to control the movement of the carrier base 51, and executes theaforesaid grease supply operation. In this embodiment, the controldevice 100 stores a calculated value of the total driven amount of thecarrier base 51 (slider 63), and when this calculated value reaches apredetermined value, it executes the aforesaid grease supply operation.This calculated value of the total driven amount can be found based on acalculated value of, for example, a total movement distance of thecarrier base 51 (slider 63) corresponding to the number of rotations ofthe motors 66. Alternatively, a calculated value of a total movementtime of the carrier base 51 (slider 63) corresponding to the operatingtime of the motors 66 may be used. When the calculated value of thetotal movement distance is adopted, the timing for the grease supplyoperation may be set, for example, every 10 Km of the movement distance.

Alternatively, the grease supply operation may be executed based on themagnitude of a torque of the motor 66, not based on the aforesaidcalculated value of the total movement amount. Specifically, when alarge amount of the grease exists between the ball screw 61 and the ballnut 62, the torque of the motor 66 required for rotating the ball screw61 is somewhat large due to the viscosity of the grease. Then, as theamount of the grease gradually reduces, the torque of the motor 66required for rotating the ball screw 61 gradually becomes smaller.Therefore, the amount of the grease can be detected based on themagnitude of this torque. In this case, the control device 100 monitorsa value of the torque of the motor 66, and an instant at which the valueof the torque reduces to a predetermined value or lower is set as theexecution timing for the grease supply operation.

The grease supply mechanism 70 as structured above is provided inplurality at places requiring periodic grease supply. For example, theball screws 61 are provided on both sides of the carrier base 51, andthe grease supply mechanisms 70 are provided for the ball screws 61 onthe both sides respectively. Further, actually, the ball screw 61 hastwo screw grooves, and the slider 63 has two ball nuts 62 for one ballscrew 61. The grease supply mechanisms 70 are provided for these twoball nuts 62 respectively. Further, the grease supply mechanisms 70 arealso provided also for portions between the two linear guides 60 and thetwo sliders 63 which are provided on both sides of the carrier base 51.

As described above, in the vacuum processing apparatus 1 of thisembodiment, it is possible to supply the grease to necessary places bythe grease supply mechanisms 70, without opening the vacuum transferchamber 10 to the atmosphere. This can reduce the work time and troubleconventionally required for the grease supply. This further eliminates aneed for the time for setting the vacuum chamber, which has been oncemade open to the atmosphere, to the vacuum atmosphere again in order toallow the resumption of the vacuum processing. Therefore, it is possibleto improve the operating rate of the vacuum processing apparatus toimprove productivity. Further, owing to the automatic supply of thegrease at preset timings, the maintenance of the grease supply is notforgotten, so that the maintenance of the grease supply can be executedwithout fail.

Next, operations for the vacuum processing in the vacuum processingapparatus 1 of this embodiment as structured above will be described.When the cassette or the FOUP is placed on the mounting part 19, anot-shown transfer mechanism provided in the transfer chamber 18 takesout the semiconductor wafer W from the cassette or the FOUP, and carriesthe semiconductor wafer W to the aligning mechanism 20 for alignment,and thereafter, puts the semiconductor wafer W in the load lock chamber17.

Then, the transfer mechanism 50 carries the semiconductor wafer W fromthe load lock chamber 17 to each of the vacuum process chambers 11 to16, where the semiconductor wafer W undergoes predetermined processing.Further, the transfer mechanism 50 carries the semiconductor wafer W,which has undergone the processing, out of each of the vacuum processchambers 11 to 16 to put it in the load lock chamber 17.

The processed semiconductor wafer W thus placed in the load lock chamber17 is thereafter taken out of the load lock chamber 17 by the transfermechanism provided in the transfer chamber 18 to be housed in thecassette or the FOUP placed on the mounting part 19.

In executing the vacuum processing as described above, the carrier base51 is linearly driven in the vacuum transfer chamber 10 which is set tothe vacuum atmosphere. The above-described control device 100 calculatesthe total driven amount of the carrier base 51 to store the calculatedvalue. Then, when the calculated value of the total driven amountreaches the predetermined value, the aforesaid grease supply operationby the grease supply mechanism 70 is executed.

As described above, according to the vacuum processing apparatus of thisembodiment, it is possible to supply the grease to predetermined places,without opening the vacuum chamber to the atmosphere, so that theoperating rate of the vacuum processing apparatus can be improved,leading to improved productivity, and it is possible to execute themaintenance of the grease supply without fail.

Next, another grease supply mechanism 80 will be described withreference to FIG. 6 and FIGS. 7A and 7B. The grease supply mechanism 80includes a cylindrical grease storage part 81 storing grease G. In aback end side of the grease storage part 81, provided is a piston 82which moves while being in contact with an inner wall of the greasestorage part 81. The piston 82 is connected to a bimetal 83 and moves inthe grease storage part 81 in the right and left direction in thedrawings in accordance with the deformation of the bimetal 83. Thegrease storage part 81 has on a lower side thereof a grease supply port84. The bimetal 83 is formed in, for example, a spiral shape. However,the bimetal 83 may have any shape as long as it can move the piston 82when its temperature rises.

When the bimetal 83 deforms in accordance with the temperature rise, thepiston 82 is pressed by the bimetal 83 to move toward the right side inthe drawings, so that the grease G is pushed out of the grease supplyport 84. FIG. 7A shows a state at room temperature, and FIG. 7B shows astate where the grease G is pushed out of the grease supply port 84 dueto the temperature rise.

The grease supply mechanism 80 is mounted adjacent to, for example, abearing mechanism 67 of the slider 63 moving along the linear guide(rail) 60. The grease supply port 84 of the grease supply mechanism 80faces the linear guide 60. Therefore, when, in accordance with themovement of the slider 63 along the linear guide 60, frictional heat isgenerated due to the insufficient grease to raise the temperature (forexample, 50° C. to 60° C.) of the bearing mechanism 67, the heat istransferred to the grease supply mechanism 80, so that the grease issupplied to the linear guide 60 from the grease supply mechanism 80. Inthis manner, when the grease becomes insufficient, the grease isautomatically supplied to the linear guide 60 from the grease supplymechanism 80. Further, the grease supply mechanism 80 can be mounted soas to supply the grease to a sliding portion between the ball screw 61and the ball nut 62. In this case, the grease supply mechanism ispreferably disposed near the ball nut 62. Consequently, when thefrictional heat is generated due to the insufficient grease to raise thetemperature (for example, 50° C. to 60° C.) of the ball nut 62 as theball screw 61 rotates and slides against the ball nut 62, the heat istransferred to the grease supply mechanism 80, so that the grease issupplied to the ball screw 61 and the ball nut 62 from the grease supplymechanism 80.

The above-described embodiment includes the grease supply mechanismsupplying the grease to the slide mechanism which is a linear drivingportion of the transfer mechanism, but it should be noted that thepresent invention is not limited to such an embodiment. It goes withoutsaying that the present invention is similarly applicable to other slidemechanisms. Further, the structure of the grease supply mechanism is notlimited to that shown in FIG. 5 or in FIG. 6 and FIGS. 7A and 7B. Thegrease supply mechanism may have any structure as long as it can storethe grease and can supply the stored grease. Further, a similar greasesupply mechanism can also be provided for a slide mechanism outside thevacuum chamber.

What is claimed is:
 1. A vacuum processing apparatus applying vacuumprocessing to an object to be processed under a vacuum atmosphere,comprising: a vacuum chamber; and a grease supply mechanism provided insaid vacuum chamber to supply grease to a slide mechanism sliding insaid vacuum chamber wherein said grease supply mechanism, comprising: agrease storage part; and a movable cover covering an opening of thegrease storage part, sliding while being in contact with an inner wallof the grease storage part, and having a grease supply port, and whereinthe cover is pressed and moved toward an inside of the grease storagepart by a predetermined distance to cause a predetermined amount of thegrease to be supplied through the grease supply port.
 2. The vacuumprocessing apparatus as set forth in claim 1, further comprising: acontrol unit which controls said grease supply mechanism to supply thegrease to the slide mechanism based on a timing for supplying the greaseto the slide mechanism, which is stored in said control unit.
 3. Thevacuum processing apparatus as set forth in claim 1, wherein the slidemechanism is provided in a transfer mechanism which transfers the objectto be processed in said vacuum chamber.
 4. The vacuum processingapparatus as set forth in claim 3, wherein the slide mechanism isconstituted of a ball screw and a ball nut included in the transfermechanism.